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Social Impact Statement: Cassava is a vital food source for millions worldwide, crucial for food security and economic stability. This study analyzed cell wall polysaccharides in cassava roots to understand their impact on cooking properties. We found these polysaccharides influence the textural attributes of cassava roots, essential for both cooking and consumption. The research highlights the need to further identify and analyze cassava cell wall components. By improving our understanding of these components, we can improve food security, affordability, and resilience in diverse regions, ultimately contributing to global food security and better aligning with consumer preferences. Summary: The textural attributes of cassava roots significantly influence preferences in cooking and consumption as a food source, yet the specific components dictating these properties remain unclear. We aimed to identify the factors shaping the cooking properties of cassava roots.We conducted a compositional analysis of 22 traits in a diverse F1 biparental population derived from soft‐ and hard‐boiling progenitors. The traits encompassed cooking qualities, starch properties, and cell wall composition.Specific cell wall components including cellulose, xylan, un‐esterified, and methyl‐esterified homogalacturonan (HG) demonstrated a correlation with cooking quality attributes: sensory assessments related to texture (SAT) and water absorption during boiling (WAB). Correlation and regression analyses revealed that these wall components collectively contribute to 20% of SAT variability and 14% of WAB variability. SAT appeared to be influenced by methyl‐esterified and un‐esterified HGs, xylan, and cellulose, impacting the tensile strength of the cell wall. Conversely, WAB appeared to be associated with methyl‐esterified HG, potentially altering water absorption properties. Although genome‐wide association studies (GWAS) were unable to identify significant SNPs for SAT and WAB, notable associations emerged for cellulose, xylan, and un‐esterified‐ and methyl‐esterified HG. Candidate genes associated with these SNPs point towards diverse cell wall‐related proteins, transcription factors, sugar metabolism‐related genes, and glycosyl hydrolases.This study provides insights into the relationship between cassava root compositions and cooking characteristics and the role of wall components in determining the cooking quality of edible cassava. This information represents a substantial contribution towards the development of protocols for selecting varieties with texture preferences. [ABSTRACT FROM AUTHOR]

Cassava (Manihot esculenta Crantz) was introduced to Southeast Asia in the 16th–17th centuries and has since flourished as an industrial crop. Since the 1980s, Thailand has emerged as the leading producer and exporter of cassava products. This growth coincided with the initiation of cassava breeding programs in collaboration with the International Center for Tropical Agriculture (CIAT), focusing on root yield and starch production. The success of Thai cassava breeding programs can be attributed to the incorporation of valuable genetic diversity from international germplasm resources to cross with the local landraces, which has become the genetic foundation of many Thai commercial varieties. Effective evaluation under diverse environmental conditions has led to the release of varieties with high yield stability. A notable success is the development of Kasetsart 50. However, extreme climate change poses significant challenges, including abiotic and biotic stresses that threaten cassava root yield and starch content, leading to a potential decline in starch-based industries. Future directions for cassava breeding must include hybrid development, marker-assisted recurrent breeding, and gene editing, along with high-throughput phenotyping and flower induction. These strategies are essential to achieve breeding objectives focused on drought tolerance and disease resistance, especially for CMD and CBSD. [ABSTRACT FROM AUTHOR]

Grafting of cassava (Manihot esculenta Crantz) understocks with scions from Manihot glaziovii was proposed to improve the cassava root yield and as a temporal approach to overcoming the problem of cassava mosaic disease (CMD). This work compared performance of nongrafted KU50 with M. esculenta grafted as understock with M. glaziovii, KU50 or HB80 scions. KU50 and HB80 are released M. esculenta varieties. Work was conducted in the field using a randomized complete block design (RCBD) with four replicates in two seasons (rainy and dry seasons) in Thailand. The M. glaziovii grafted plants were larger than nongrafted controls. Grafting also increased fresh root yield by 25% (dry season) and 37% (rainy season) and dry matter content by 19% (dry season) and 42% (rainy season) over the nongrafted controls. Net photosynthesis (Pn), stomatal conductance (gs) and growth parameters indicated that the grafted plants had a higher photosynthetic capacity and more vigorous growth than nongrafted controls during the dry season. Correlation coefficients of Pn and gs with growth and productivity parameters at different ages of the plant were highly significant during the dry season but not in the rainy season. This study demonstrated that M. glaziovii–cassava grafting improved cassava growth and root yield. [ABSTRACT FROM AUTHOR]

Breeding for consumers preferring grain qualities has become a chief goal for rice breeding programs in the world. Amylose content (AC) and aroma are important qualities for consumers' preference and market price. To introgress the alleles of waxy (Wxb) and fragrance (badh2) genes into Sinthukha, a widely adaptable high-yield rice variety in Myanmar which has intermediate AC and non-aroma, RNP20-145-1-9 line was used as a donor parent, and pseudo-backcross breeding was designed to shorten the backcross program. In this approach, only one backcross (BC1F1) and one self-pollinated (BC1F2) population was generated to select for the plants with donor alleles of waxy and fragrance genes in foreground selection, and the selected plants were screened for the highest percentage of recurrent genome content (%RGC) in background selection by amplified fragment length polymorphism (AFLP) analysis. The progenies with the highest %RGC, 84% and 92% were selected in BC1F1 and BC1F2 populations, respectively, and these selected plants possessed heterozygous alleles in fragrance and waxy genes. The agronomic and yield performance, grain size and shape of selected BC1F2 plants were most similar to those of Sinthukha. Nevertheless, amylose content of the selected plants was as low as that of RNP20-145-1-9 rice line. In this study, marker-assisted pseudo-backcross approach was useful in the introgression of low amylose and aroma genes from RNP20-145-1-9 line into Sinthukha, and it could accelerate backcross breeding program through the combination of marker-assisted foreground and background selections. AFLP analysis could save not only time consumption but also the cost of analysis and workload in background selection. [ABSTRACT FROM AUTHOR]

<b>Background and Objective:</b> <i>Flowering locus T</i> (<i>FT</i>) genes are involved in the flower induction mechanism in plants as florigen signals. The objective of this study was to study the relationship between the expression of <i>Flowering locus T</i> genes (<i>MeFTs</i>) in cassava and flowering traits under the different flowering induction conditions. <b>Materials and Methods:</b> The experimental design for flowering induction was RCBD for 4 replications. There were 5 treatment factors which were control, red light set from 5 pm to 7 am, 0.5 mM 6-benzyladenine (BA) with 2 mM silver thio-sulfate (STS), paclobutrazol for 6 g/plant and potassium chlorate (KCIO<sub>3</sub>) for 250 g/plant. The number of plants with flower bunches and the average number of bunches per plant in two cassava varieties were collected each month from 5-9 months after planting (MAP). The leaf samples were collected from HB80 and R9 varieties at 5-7 MAP for RNA extraction to study <i>MeFT1</i> and <i>MeFT2</i> expression. <b>Results:</b> The results show that <i>MeFT1</i> expression level positively correlated with flowering traits in the same month, while <i>MeFT2</i> expression level positively correlated with flowering traits in the following months. <b>Conclusion:</b> Therefore, expression of <i>MeFT2</i> can be used for the prediction of cassava flowering in the following month which will assist the breeder for the crossing management.

In Asia, cassava ( Manihot esculenta ) is cultivated by more than 8 million farmers, driving the rural economy of many countries. The International Center for Tropical Agriculture (CIAT), in partnership with national agricultural research institutes (NARIs), instigated breeding and agronomic research in Asia, 1983. The breeding program has successfully released high-yielding cultivars resulting in an average yield increase from 13.0 t ha -1 in 1996 to 21.3 t ha -1 in 2016, with significant economic benefits. Following the success in increasing yields, cassava breeding has turned its focus to higher-value traits, such as waxy cassava, to reach new market niches. More recently, building resistance to invasive pests and diseases has become a top priority due to the emergent threat of cassava mosaic disease (CMD). The agronomic research involves driving profitability with advanced technologies focusing on better agronomic management practices thereby maintaining sustainable production systems. Remote sensing technologies are being tested for trait discovery and large-scale field evaluation of cassava. In summary, cassava breeding in Asia is driven by a combination of food and market demand with technological innovations to increase the productivity. Further, exploration in the potential of data-driven agriculture is needed to empower researchers and producers for sustainable advancement., (Copyright © 2020 by JAPANESE SOCIETY OF BREEDING.)